72643390 has 32 divisors (see below), whose sum is σ = 136515456. Its totient is φ = 27805440.

The previous prime is 72643387. The next prime is 72643399. The reversal of 72643390 is 9334627.

It is a super-2 number, since 2×72643390² = 10554124221384200, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72643399) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20059 + ... + 23401.

It is an arithmetic number, because the mean of its divisors is an integer number (4266108).

Almost surely, 2^72643390 is an apocalyptic number.

72643390 is a deficient number, since it is larger than the sum of its proper divisors (63872066).

72643390 is a wasteful number, since it uses less digits than its factorization.

72643390 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3444.

The product of its (nonzero) digits is 27216, while the sum is 34.

The square root of 72643390 is about 8523.1091744738. The cubic root of 72643390 is about 417.2522631764.

The spelling of 72643390 in words is "seventy-two million, six hundred forty-three thousand, three hundred ninety".